Desert rainbowfish

Melanotaenia splendida tatei

Also known as Tate's rainbowfish

FreshwaterFish

Care at a glance

Temperature: 64–86°F (18–30°C)
pH: 6.8–8.2
Adult size: 3.9 in (10 cm)
Minimum tank: 42 gal (160 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Easy
Breeding: Easy
Rarity: Rare
Origin: Lake Eyre and Bulloo drainages, central Australia
Family: Melanotaeniidae

Overview

This is the toughest of the rainbowfishes to keep, an adaptable, peaceful schooler that tolerates cooler rooms and hard water that would trouble tropical species. Keep a group of six or more for natural shoaling and the best male color, and pair it with other hardy, peaceful community fish of similar size. It eats almost anything offered: flake, granules, frozen bloodworm and daphnia, and some green food. A tank of at least 160 liters with open water for swimming suits an active group, and it does not strictly need a heater in a warm room.

In the wild

The desert rainbowfish lives in the boom-and-bust rivers and waterholes of central Australia's Lake Eyre and Bulloo basins, water that can be cool at night and very warm by day. It shrugs off a wide range: 18 to 30 degrees Celsius and a pH of 6.8 to 8.2, hard and alkaline. A tank with a sandy bottom, some rock and wood, and open water reflects its harsh, sun-baked home.

Good to know

Melanotaenia splendida tatei is the inland subspecies of the splendid rainbowfish complex, family Melanotaeniidae, reaching about 10 centimeters. It endures temperature and salinity swings that would kill most rainbowfishes. Breeding is easy: when conditions improve, as after a flood, groups spawn heavily, scattering sticky eggs on plants and mops, and the fry are hardy by rainbowfish standards.

Did you know

Populations survive in isolated desert waterholes that may bake for years between floods, then breed heavily when the rains finally come, which makes this fish a favorite subject for scientists studying how animals cope with extreme, unpredictable water.